Water heaters and heat pumps are well known devices that are used world wide. Prior art heat recovery devices such as that disclosed in U.S. Pat. No. 4,599,870 to Hebert et al., the disclosure of which is hereby incorporated in its entirety by reference, have been developed to recover the heat produced by a heating, ventilation and air conditioning unit (hereinafter “HVAC unit”). This recovered heat may be utilized to heat water for a variety of purposes such as providing hot water for residential or commercial use. Some of these devices use a pumpless thermosyphon heat transfer system to remove cold water from the tank of the water heater and reintroduce heated water into the tank. The use of these heat recovery units is environmentally friendly and reduces energy consumption.
Unfortunately, prior art heat recovery devices typically require a professional installer to couple the HVAC units to the water heating system. The large number of connections made in such an installation also increase the likelihood that a leak will occur. In addition, the pumping rate of the thermosyphon heat transfer system and, thus, the heat transfer rate of the system, is often less than desired. Therefore, what is needed is an improved heat recovery system that is easier to couple to an existing HVAC system, less likely to leak and has a higher rate of heat transfer.